const set_cookie = (name, value, days) => {
    const expires = new Date(Date.now() + days * 86400 * 1000).toUTCString();
    document.cookie = `${name}=${value}; expires=${expires}; path=/;`;
  }

window.onload = async () => {
    alert("This service requests a captcha from https://ofd.ru and sends an example receipt to it to check the correctness of the captcha. If you are not okay with making such requests, please leave the site immediately");
    
    if (document.cookie.includes('JWT')) {
        document.location = '/';
    }

    const form = document.getElementById("loginForm");
    const username = document.getElementById("username");
    const password = document.getElementById("password");
    form.addEventListener('submit', async (e) => {
        e.preventDefault();
        const response = await fetch(
            `/api/user/login`, { 
            method: "POST", 
            headers: { 
                'Content-Type': 'application/json' 
            }, 
            body: JSON.stringify({ 
                "username": username.value, 
                "password": password.value 
            }) 
        });
        switch (response.status) {
            case 403:
                alert("Incorrect password");
                password.value = "";
                break;
            case 200:
                response_json = await response.json()
                set_cookie("JWT", response_json["token"], 365);
                window.location.href = '/';
                break;
            case 404:
                alert("No such user exists");
                username.value = "";
                break;
            default:
                alert("Unknown server error. Please, conact the developer");
                console.log(response);
        }
    });
};